Helicopter with jet-propelled rotor



De@o 9, i952 p, H, L, MOR/MN 2,620,882

HELICOPTER WITH JET-PROPELLED ROTOR Filed Aug. l, 1947 2 Sl-IEETS-SHEET1 hul 'Hemi Lon. Yfuvmva.,

EQ... #gw/wv Dec. 9, 1952 p H L, MQRMN 2,520,882

HELICOPTER WITH JET-PRQPELLED ROTOR Filed Aug. l, 1947 2 slams-SHEET 2IJ i 1 45 \Zd" h J9 35 'f mi j Inventor:

PAUL HENRI LEON HORAII,

Patented Dec. 9, 1952 UNITED STATES PATENT OFFICE Application August 1,1947, Serial No. 765,467 In France September 26, 1944 Section 1, -PublicLaw 690, August 8, 1946 Patent expires September 26, 1964 (Cl. 170-135A)4 Claims.

My invention relates to helicopters with jetpropelled rotor.

It has already been suggested to arrange a pulse-jet power unit at ornear the tip of each rotor blade and to utilize their jet-reactionmotive force to propel the rotor. The application of such pulse-jetpower units resulted however in many serious disadvantages particularlyin view of their intricate design and of the varying propulsion thrustowing to the intermittent rmg.

The main object of my invention is to avoid the said disadvantages andto provide helicopters with jet-propelled rotors which are simplev andreliable in construction and capable to operate continuously and inwhich the fuel supply to the power-units is metered and controlled bythe rotating rotor.

According to my invention I provide a ram-jet reaction power unit orathodyd at or near the tip of each propeller arm or blade and I regulatethe fuel supply thereto in accordance with the orbital position of eachof said power units in such manner that fuel is supplied thereto invariable time intervals at least while the power unit advances in itsrotational movement in the direction of the forward movement of thehelicopter.

The said and other objects of my invention will be more fully understoodfrom the following specication when read with the accompanying drawingin which Fig. 1 is a schematic perspective view of a helicopter,

Figs. 2 and 3 show in a vertical axial section and in a top view,respectively, the rotor hub mounted upon the rotor shaft and one rotorarm or blade with a ram-jet propulsion unit or athodyd attached theretoat the top thereof,

Fig. 4 is a developed view of a cylindrical cam for the cyclical controlof the fuel supply to the athodyd,

Fig. 5 illustrates in a schematic perspective view, partly in section,an electric regulating mechanism for the fuel supply to the athodyd, and

Fig. 6 shows schematically in a longitudinal sectional a ram-jetpropulsion unit or athodyd for propelling the rotor according to myinvention.

The same reference characters indicate the same or equivalent parts inall figures of the drawing.

Fig. l of the drawing shows diagrammatically a helicopter comprising aconventionally shaped body or fuselage I and a rotor having forginstancethree arms or blades 2 rotatable about 2 the axis 3-3' of the rotorshaft. The tip of each rotor blade or arm 2 supports a ram-jetpropulsive unit or athodyd 4 which causes the rotor to rotate in thedirection of the arrow 5 by the reaction force against the "surroundingatmosphere. As known in the art such ram-jet propulsive units (athodyds)to become operative have to receive a certain initial velocity which maybe imparted thereto by any known and suitable means. The fuselage I isrearwardly provided with vertical and horizontal tail-ns 6 and '1,respectively, adapted to impart satisfactory stability thereto. Moreoverthe vertical tail-fm 6 is provided with a pivoted flap 6' the setting ofwhich eiects the compensation of the friction torque which tends tocarry the fuselage around in the direction of rotation of the rotor.

The rotor arms 2 rotate about said axis 3-3 either in a planeperpendicular thereto or in conical superficies and the intersectingpoint of the longitudinal axes of each arm 2 and of the athodyd attachedthereto, respectively, moves in a circular path indicated by the dottedline 8. The longitudinal axis of each athodyd is tangential to saidcircular path 8. If the angle between the m'ost advanced position of thelongitudinal axis of a rotor arm 2, considered in the direction of theforward lspeed V of the helicopter, and a temporary orbital position ofsuch axis during the rotation of the rotor arm 2 is indicated by thereference 6 then it will be well understood that the momentary relativespeed of the athodyd in respect to said forward speed V of thehelicopter will be defined by the equation U-V.sin 0 wherein U indicatesthe peripheral speed of the athodyd along its circular path. The saidrelative speed U-Vsin 0 will reach a maximum value when 0 equals or 270and at or near this position each athodyd will react with highestefficiency upon the respective rotor arm. Therefore the most effectivesupply of fuel to the athodyds will occur when the respective rotor armis at or in the neighborhood of said position that is in the timeinterval which includes said position deiined by 0=270. The continuousrotation of the rotor will be ensured by the successive action of theindividual athodyds upon the respective rotor arms and by the inertia ofthe rotor which is greater than that of hitherto conventional rotors inView of the additional mass of the power units arranged at the top ofeach rotor arm'. The said cyclically interrupted fuel supply to theathodyds provides the further advantage of an efficient cooling betweensucceeding rings and consequently the application of highertemperatures. From the foregoing it will be well understood that thedrive power of the rotor may be controlled by varying the said fuelsupply period which, however, if necessary may coincide with a fullrotation of the rotor to effect a continuous operation of the powerunits. It is further contemplated according to my invention to controlthe start of an adjusted fuel intake period with regard to the initialposition of the power units.

Figs. 2 and 3 illustrate one arm of the rotor which rotates about theshaft 9 stationary mounted in the fuselage l. Each rotor arm 2 comprisesa shaft I4 which is with its inner forked end connected to the rotor hubI2 by means of a universal joint I3 and which has rigidly connected toits tips a ram-jet propulsion unit or athodyd 4. The rotor hub I2 issupported on the rotor shaft 9 by ball bearings I0 and II. Each of saidarm shafts I4 supports rotatably by means f ball bearings I 5 and I 1 atubular shaft I5 to which the actual rotor blade 2 is fixed. The pitchof the blades 2 may be controlled by a lever I8 connected to aconventional mechanism not shown in the drawing for example of the typedisclosed in Hafner-s Patent No. 2,150,969.

The rotor shaft 9 is provided with an axially extending duct I9connected to the fuel supply tank not shown in this figure but shown inFigs. 5 and 6 and marked 8l. A port 28 in said duct I 9 connects thesame with a circular distribution chamber 2I arranged in the rotor hubI2. A tight seal is maintained between the rotor hub I 2 and the rotorshaft 9 for example by the rotary joints 22 to prevent any escape offuel from said chamber 2I. Each rotor arm shaft I4 is provided with anaxial duct 24 leading with one end into the athodyd 4 and connected atits other end to said distribution chamber 2| by means of a flexiblepiping or other connection 23 which bypasses the universal joint I3.

The control means for the fuel supply to the athodyds as shown in Figs.2 and 3 comprise a cylindrical bush 25 which is adjustably mounted uponthe rotor shaft 9. The position of said bush 25 relative to the rotorshaft 9 may be adjusted in axial direction as well as angularly byproper and well known means which are not illustrated. Said bush 25 isprovided with a circumferential cylindrical cam portion 26 whichcooperates with follower rollers 21 each of which actuates a check valve18 in the fuel supply line leading to one athodyd, for example withinthe flexible connection 23. Each follower roller 21 is mounted upon onearm of a lever 28 swingable about the pin 29 which rests in a projection19 of the rotor hub I2 and rotates therewith. A Ispring 3| acting uponthe other arm of said lever 28 presses the roller 21 against the surfaceof the bush 25. The rollers 21 driven around the bush 25 by the rotatingrotor hub I2 are thus lifted from the .cylindrical surface of the bush25 in a plane perpendicular to the axis 3-3 of the rotor shaft 9 if andwhen the roller 21 runs upon the raised cam portion 26 thereof thuscausing said swing arm 28 to tilt about the pin 29. This tiltingmovement of the lever 28 is utilized to effect the opening and closingof the said check valve 18 within the fuel supply line leading to theathodyd 4 for example in the piping 23. To this effect said valve 18 isconnected to and actuated by said lever 28 in such manner that the valve'I8 4 is opened when the roller 21 is lifted by the cam 26. However saidvalve 18 may be actuated by said roller 21 or its supporting lever inany other suitable manner by mechanical, hydraulic, pneumatic orelectric means known per se in the art.

Fig. 4 shows the developed view of the cam 26 raised from thecylindrical surface of the bush 25. As illustrated the effective camcontour 32 may for example have the shape of a sinusoidal curve.According to the axial position of the bush relative to the rotor shaft9 each of the rollers 21 will ride around the bush 25 along anycircumferential path such as indicated for example by the lines 33-33',311-34', 35-35, 36-36. When the rollers 21 ride along thecircumferential line 33-33' avoiding the raised cam portion 26, theroller arms 28 will not be tilted and will not actuate the valve 18 forthe fuel supply thus preventing any fuel delivery to the athodyds duringthe entire revolution of the rotor. If the rollers 21 ride along theline 34-34 a short fuel supply will be effected while the rollers passover the cam between the points 31, 31. While riding along the line35-35 the rollers 21 will effect a fuel supply to each athodyd lastingfor about a half revolution of the rotor. And while riding along theline 35-36 situated entirely below the contour line 32 of the cam therollers 21 will remain lifted from the cylindrical lsurface of the bush25 and the fuel supply to each athodyd will continue during the fullrevolution of the rotor. Accordingly the axial displacement of the bush26 along the rotor shaft 9 makes it possible to completely control thefuel supply to the athodyds from a complete shut off to a continuoussupply during a full revolution 0f the rotor. In addition thereto anangular displacement of the bush 25 relative to the rotor shaft 9 willpermit to adjust the start of the fuel intake period by the athodydsduring their revolution.

Fig. 5 illustrates schematically partly in section an electricallyoperated control mechanism for the fuel supply to each athodyd whichmechanism may be substituted for the mechanically operating controlmechanism shown in Figs. l and 2 and described above. ln fact the Fig. 5

iould be considered for better understanding together with the morecomplete Figs. 1 and 2. Fig. 5 shows a portion of the rotor hub I2 andof the distributing chamber 2| arranged therein. The fuel is supplied tosaid chamber 2i through a pipeline 88 from a fuel tank 8i and passesthereafter through a valve 18 arranged in a connecting piping 23 whichleads into the axial duct 24 of each arm shaft I Il and from there intothe respective athodyd 4. The Valve 18 as illustrated is a pin valvecomprising a pin 56 attached to a valve rod and sealed in the valve bodyby a packing ring 58. A helical spring 51 keeps the valve in closedposition. The valve is opened by the action of the solenoid 54 whichlifts the valve rod 55 when energized by electric current incomingthrough the wire 53 which is connected to the swing lever 28. This swinglever 28 is rotatable about the pin 28 mounted in a projection 19 of therotor hub I2. One arm of said lever 28 carries an electric brush 52which is pressed against the slipring 25 by the force of a spring 3|acting upon the other arm of said swing lever. The said slipring 25 ismounted upon the rotor shaft 9 and may be axially and/or angularlyadjusted thereupon as explained above with regard to the bush 25 shownin Figs. 2 and 3. The cylindrical surface of said slipring 25 is dividedin an electrically conductive surface portion 5l and an electricallynon-conductive surface portion which surface portions adjoin each otheralong an essentially sinusoidal line as shown in Fig. 4, the raised camportion 26 referred to earlier corresponding to the electricallyconductive surface portion 5|. It will be well understood that thebrushes 52 will run along a, shorter or longer path on the electricallyconductive Surface portion 5l according to the axial position of theslipring with regard to said brush and While doing so will close theelectric circuit energizing the solenoid 54 and thereby actuating thevalve 78 for a shorter or longer period as explained above with regardto Fig. 4.

Fig. 6 shows schematically a longitudinal section through a ram-jetpropulsion unit or athodyd mounted at the outer end of each rotor wing2. Each athodyd comprises a combustion chamber within streamlined walls.The air enters into the combustion chamber through the frontal intakeopening 38 and the combustion gases leave said chamber through the rearexhaust opening 42. The incoming air is compressed and has its velocitycommuted into the static pressure or ram while passing through thedivergent portion 39 of the combustion chamber into the burner section50. The fuel which is taken from a storage tank 8i by a conduit 80 isintroduced into the said combustion chamber through the duct 24 arrangedin each rotor WingI shaft I4 (see Fig. 2) and is atomized therein by aninjector 43. The fuel burns continuously in the said central burnersection B0 of the combustion chamber and the pressure energy of thecombustion gases is transformed into kinetic energy while said gasespass through the convergent conical section 4I of the combustion chambertowards the exhaust 42. A spark plug 45 serves to start the combustionof fuel within the combustion chamber and the power unit thereafteroperates continuously.

Having shown and described specific embodiments of my invention toillustrate the application of the principles thereof it will be wellunderstood that my invention may be constructed in various otherembodiments which come within the scope of the appended claims.

What I claim as my invention is:

1. In a helicopter with a rotor propelled by jetreaction power units theimprovement comprising in combination a plurality of rotor blades;ramjet propulsion units or athodyds containing a combustion chambersituated between a divergent and a convergent duct; each propulsion unitmounted at the tip of one rotor blade; the common longitudinal axis ofsaid ducts being essentially tangential to the circle of rotationdescribed by the ends of the rotor blades; a fuel tank; conduitsconnecting said tank and each of said combustion chambers; regulatingmeans in each of said conduits to control the fuel supply passingtherethrough; and actuating means for said regulating means operablyassociated therewith and with said rotor and operated in accordance withthe orbital position of the ram-jet unit to coincidentally control theinjection of fuel into the combustion chamber in such manner that thefuel is supplied in variable time intervals at least while the rotorblade supporting the respective ram-jet unit advances in its rotationalmovement in the direction of the forward movement of the helicopter.

2. In a helicopter with a rotor propelled by jetreaction power units theimprovement comprising in combination a fuselage; a fixed shaftupstanding from said fuselage; a rotor hub rotatably mounted on saidshaft; radially extending arms jointed to said hub; a ram-jet power unitor athodyd mounted at the tip of each of said arms; a pitch-variablerotor blade mounted upon each of said arms; a fuel tank; conduitsconnecting said tank with each of said ram-jet power units; saidconduits passing through said shaft, said hub and each of said arms; avalve in each of said conduits to control the fuel supply to each ofsaid power units; and actuating means for said fuel supply valvesoperably associated therewith and with said rotor` and operated inaccordance with the orbital position of the ram-jet unit tocoincidentally control the injection of fuel into the ram-jet unit insuch manner that the fuel is supplied in variable time intervals atleast While the rotor blade supporting the respective ram-jet unitadvances in its rotational movement in the direction of the forwardmovement of the helicopter.

3. In a helicopter according to claim 2, actuating means for the fuelsupply valves comprising a sinusoidal cam mounted on said shaft;camfollower means cooperating therewith; each of said cam-follower meansjointed to said rotor hub and actuating one of said fuel supply valves;and means to vary the langular and axial setting of said cam on saidshaft to adjust the cooperation between said cam and its followers inorder to regulate the fuel supply.

4. In a helicopter according to claim 2, actuating means for the fuelsupply valves comprising a plurality of solenoids each actuating onevalve; a slipring slidably and rotatably mounted on said shaft andelectrically insulated therefrom; the cylindrical surface of saidslipring having an electrically conducting surface portion and anonconductive surface portion; said surface portions adjoining eachother along a sinusoidal line; a plurality of contact brushes slidingupon the cylindrical surface of the slipring and each electricallyconnected with one solenoid; the contact brushes beiner supported bysaid rotor hub; an electric circuit connecting said slipring, saidbrushes and said solenoids; and means to vary the angular and axialsetting of said slipring upon said shaft to adjust the cooperationbetween the slipring and the brushes in order to regulate the action ofthe solenoids actuating the fuel supply valves.

PAUL HENRI LE'ON MORAIN.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,820,946 Pitcairn Sept. 1, 19312,084,464 Stalker June 22, 1937 2,142,601 Bleecker Jan. 3, 19392,330,056 Howard Sept. 21, 1943 2,397,357 Kundig Mar. 26, 1946 2,438,151Davis Mar. 23, 1948 FOREIGN PATENTS Number Country Date 47,909Netherlands Mar. 15, 1940 227,151 Great Britain Jan. 12, 1925 423,590France Feb. 20, 1911 439,805 Great Britain Dec. 6, 1935 554,906 GermanyNov. 2, 1932 865,452 France Feb. 24, 1941

